On Mon, Jan 17, 2011 at 10:12:51AM +0800, tom z wrote: > What's the meaning of the "Event number". Is it number of the device's > I/O event? If the number is greater to zero, it means the I/O request's > happening? No. Just means something happened that userspace ought to know about, like a path failing. Used by 'wait' - see 'man dmsetup' and http://people.redhat.com/agk/talks/FOSDEM_2005/text51.html . Alasdair -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel